KR101980776B1 - Optical film, flat display device comprising the same, and method for manufacturing the same - Google Patents

Abstract

According to one embodiment of the present invention, there is provided an optical film that can be provided on a display surface of a flat panel display, comprising: a base layer; A pattern layer formed on at least one surface of the base layer; First and second cover layers formed on both sides of the base layer to cover the pattern layer; And a phase retardation layer formed on one surface of the first and second cover layers.
Here, the pattern layer may be a linearly polarized light pattern formed of a light absorbing material adsorbed on at least one surface of the base layer, stretched in one direction together with the base layer, and rearranged to have a linear shape in one direction; And a semi-transmissive pattern formed of a metal dispersant applied on at least one side of the base layer.

Description

TECHNICAL FIELD [0001] The present invention relates to an optical film, a flat panel display including the same, and a method of manufacturing a polarizing film.

The present invention relates to an optical film, a flat panel display including the same, and a method of manufacturing an optical film.

As the era of informationization becomes full-scale, the display field for visually displaying electrical information signals is rapidly developing. Accordingly, studies have been continuing to develop a variety of flat display devices such as large-sized, thin, lightweight, and low power consumption.

Typical examples of such flat panel display devices include a liquid crystal display device (LCD), a plasma display panel (PDP), a field emission display (FED) An electroluminescence display device (ELD), an electro-wetting display device (EWD), and an organic light emitting display device (OLED).

Such a flat panel display device includes a flat panel display panel including a pair of substrates bonded together with a unique luminescent material or a polarizing material therebetween. Here, the flat panel display panel generally includes a reflective layer for adjusting the light path so that light is emitted toward the display surface side.

However, the reflective layer reflects not only the light emitted from the flat panel display panel (hereinafter referred to as "display light") but also the light incident from the outside (hereinafter referred to as "external light"), .

Accordingly, the flat panel display device includes at least one optical film formed on the display surface in order to prevent reflection of external light and improve image quality. Illustratively, the optical film may include a polarizing layer selectively transmitting light in a predetermined direction.

Alternatively, the mirror function may be added to the off-state flat panel display device by positively utilizing external light reflection. In this case, the optical film of the flat panel display further includes a separate transflective layer for selectively reflecting light.

As described above, since a separate semi-transparent layer and an adhesive layer for fixing the semi-transparent layer to the polarizing layer are further included, it is difficult to reduce the thickness of the optical film and the flat panel display device including the same, There is a problem that luminance of light is lowered, manufacturing cost is increased, and manufacturing process becomes complicated.

The present invention is directed to an optical film capable of adding a mirror function to a flat panel display device without a separate transflective layer, a method of manufacturing the same, and a flat panel display device that can be used as a mirror in a turn off state.

According to an aspect of the present invention, there is provided an optical film that can be provided on a display surface of a flat panel display, including: a base layer; A pattern layer formed on at least one surface of the base layer; First and second cover layers formed on both sides of the base layer to cover the pattern layer; And a phase retardation layer formed on one surface of the first and second cover layers. Here, the pattern layer may be a linearly polarized light pattern formed of a light absorbing material adsorbed on at least one surface of the base layer, stretched in one direction together with the base layer, and rearranged to have a linear shape in one direction; And a semi-transmissive pattern formed of a metal dispersant applied on at least one side of the base layer.

A method of manufacturing an optical film that can be provided on a display surface of a flat panel display, the method comprising: providing a base layer; Forming a pattern layer on at least one side of the base layer; Forming first and second cover layers on both sides of the base layer to cover the pattern layer; And forming a phase retardation layer on one surface of the first and second cover layers. The forming of the pattern layer may include: a step of adsorbing a light absorbing material on at least one surface of the base layer; Applying a metal dispersant on at least one side of the base layer so as to form a transflective pattern selectively transmitting light; And stretching the base layer in one direction so that the light absorbing material adsorbed on at least one side of the base layer is rearranged in a straight line shape in one direction to form a linearly polarized light pattern.

In addition, a flat panel display device including a mirror function, comprising: a flat panel display panel for emitting display light for displaying an image on a display surface; And an optical film formed on the display surface of the flat panel display panel and emitting the display light to the outside and selectively reflecting at least a part of the external light.

Here, the optical film may include a base layer extending in one direction; A pattern layer formed on at least one surface of the base layer; First and second cover layers formed on both sides of the base layer to cover the pattern layer; And a phase delay layer formed on one surface of the first and second cover layers, wherein the pattern layer is adsorbed on at least one surface of the base layer, is stretched in the one direction along with the base layer, A linearly polarized light pattern formed of a light absorbing material having a linear shape in one direction; And a semi-transmissive pattern formed of a metal dispersant applied on at least one side of the base layer.

The optical film according to an embodiment of the present invention may include a transflective layer made of a metal dispersant applied on one side of the base layer together with a linearly polarized light pattern instead of a separate transflective layer for transmitting display light and reflecting external light And a pattern layer including the pattern layer.

As a result, the thickness can be thinner, the manufacturing process becomes simpler, and the manufacturing time can be shortened.

The flat panel display device including such an optical film may further include a mirror function, while preventing deterioration of image quality due to a separate transflective layer and an adhesive layer for attaching the same.

1 is a cross-sectional view of an optical film according to an embodiment of the present invention.
2 is a plan view showing the pattern layer of FIG.
3 is a cross-sectional view illustrating a flat panel display device according to an embodiment of the present invention.
4A is an optical path in a turn-on state in the flat panel display device of Fig.
Fig. 4B is an optical path in a turn-off state in the flat panel display device of Fig.
5 is a flowchart illustrating a method of manufacturing an optical film according to an embodiment of the present invention.
6 and 7 are process diagrams of Fig.

Hereinafter, an optical film, a flat panel display including the same, and a method of manufacturing an optical film according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, an optical film according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG.

FIG. 1 is a cross-sectional view illustrating an optical film according to one embodiment of the present invention, and FIG. 2 is a plan view showing a pattern layer of FIG.

1, the optical film 10 according to one embodiment of the present invention includes a base layer 11, a pattern layer 12 formed on at least one side of the base layer 11, a base layer 11, First and second cover layers 13 and 14 formed on both surfaces of the first and second cover layers 13 and 14 and covering the pattern layer 12, (15).

The base layer 11 is a sticky transparent layer. Illustratively, the base layer 11 may be a PVA film (Poly Vinyl Alcohol film).

The pattern layer 12 is formed on at least one surface of the base layer 11 and includes a linearly polarized light pattern for polarizing light and a transflective pattern for selectively transmitting and reflecting light.

As shown in Fig. 2, the pattern layer 12 is a pattern in which the linearly polarized light pattern 12a and the semi-transparent pattern 12b are scattered.

The linearly polarized light pattern 12a is formed of a light absorbing material adsorbed on the base layer 11 and rearranged to have a linear shape in one direction. Here, the light absorbing material may be an iodine complex material.

Illustratively, the linearly polarized light pattern 12a includes an iodine composite material that is a light absorbing material on at least one side of the swelled base layer 11, and an iodine-based composite material that is boric acid for crosslinking the molecular structure of the base layer 11. [ The base layer 11 is stretched in one direction, and the iodine composite material is rearranged in a straight line shape in one direction.

The semi-transparent pattern 12b is formed of a metal dispersing material applied on at least one surface of the base layer 11. [

Here, the metal dispersing member 12b is formed of a metal such as Ag, Au, Cu, Al, Pt, Ni, Pb, Co, An electrolyte containing at least one of Rh, Ru, Sn, Ir, Pd and Ti, or WGP (White Gold Plated metal).

In addition, the particle size and the coating rate of the metal dispersant 12b are variables that affect the light transmittance and the light reflectance of the optical film 10. That is, the larger the particle size of the metal dispersing member 12b or the coating rate of the metal dispersing member 12b is, the lower the light transmittance of the optical film 10 is.

Here, the light transmittance and the light reflectance correspond to each other. In order for the optical film 10 to be appropriately used for display light transmission and external light reflection, it is necessary to adjust the light transmittance and the light reflectance of the optical film 10 to 40% or more, respectively.

Thus, the particle size and the coating rate of the metal dispersing material 12b are adjusted so that the optical film 10 exhibits a light transmittance of 40 to 60%.

In one example, the particle size of the metal dispersant 12b may be 5 to 150 nm. At this time, the smaller the particle size of the metal dispersant 12b, the easier it is to control the coating rate and the light transmittance.

It is a matter of course that the particle size of the metal dispersing material 12b can be variously adjusted depending on the target light transmittance of the optical film 10, the material of the metal dispersing material 12b and the thickness of the base layer 11. [

As another example, if the metal dispersive material 12b is an electrolyte containing aluminum (Al), the semi-transparent pattern 12b may be formed to a thickness of 150 ANGSTROM. As a result of simulation in this case, the light transmittance of the optical film 10 was 40%.

The first and second cover layers 13 and 14 are formed on different surfaces of the base layer 11 to cover the pattern layer 12. The first and second cover layers 13 and 14 protect the base layer 11 and the pattern layer 12 formed on at least one surface thereof from foreign matter penetration and surface damage. Illustratively, each of the first and second cover layers 13,14 may be a TAC film (triacetylcellulose film).

The phase delay layer 15 is formed on one surface of one of the first and second cover layers 13 and 14, for example, on the back surface of the second cover layer 14, and delays the light by? / 4 phase . Thus, the light having passed through the phase delay layer 15 is circularly polarized in a clockwise or counterclockwise direction.

As described above, the optical film 10 according to one embodiment of the present invention includes the transflective pattern 12b formed of the dispersed metal dispersant together with the linearly polarized light pattern 12a on the base layer 11, A separate transflective layer for selectively transmitting and reflecting light and an adhesive layer for attaching it can be removed. As a result, not only the thickness of the optical film 10 can be thinner than the conventional one, but also the attaching step is eliminated once, and the manufacturing process can be further simplified.

Next, a flat panel display device according to an embodiment of the present invention will be described with reference to FIGS. 3, 4A, and 4B. FIG.

3 is a cross-sectional view illustrating a flat panel display device according to an embodiment of the present invention. 4A is an optical path in a turn-on state in the flat panel display device of FIG. 3, and FIG. 4B is an optical path in a turn-off state in the flat panel display device of FIG.

As shown in FIG. 3, the flat panel display 1 according to one embodiment of the present invention includes a flat panel display panel 20 and an optical film 10 formed on the display surface thereof. Here, since the optical film 10 is the same as that described with reference to Figs. 1 and 2, a duplicate description will be omitted below.

The flat panel display panel 20 includes first and second substrates 21 and 22, a light emitting layer 23 interposed therebetween, and a light emitting layer 23 formed on the side opposite to the display surface with reference to the light emitting layer 23 Reflective layer 24.

Here, the light emitting layer 23 may be a self-light emitting element that emits light based on a driving signal, or may be a polarizing element that selectively transmits light. Although not shown in detail in Fig. 3, when the light emitting layer 23 is a polarizing element, the flat panel display 1 may further include a backlight unit.

The reflective layer 24 reflects the light of the light emitting layer 23 to the display surface side. The reflective layer 24 may be formed between any one of the first and second substrates 21 and 22 and the light emitting layer 23 or may be formed on one surface of any one of the first and second substrates 21 and 22 .

As shown in Fig. 4A, when the flat panel display 1 is in a turned-on state, the light emitting layer 23_on emits display light (DL) based on a driving signal. At this time, the display light DL passes through the phase delay layer 15 and the pattern layer 12 and is emitted to the outside. That is, a part of the display light DL in a first direction (indicated by a horizontal arrow in Fig. 4A) coinciding with the linearly polarized light pattern (12a in Fig. 2) is selectively transmitted and emitted to the outside.

At this time, outgoing light OL (hereinafter referred to as "outside light") incident from the outside to the light emitting layer 23 side is reflected by the reflective layer 24, but is reflected by the pattern layer 12 and the phase delaying layer 15 It is not released to the outside again.

That is, a part of the external light OL in the first direction coinciding with the linearly polarized light pattern 12a is transmitted to the light emitting layer 23_on side, and is circularly polarized clockwise by the phase delay layer 15. The circularly polarized external light in the clockwise direction is reflected by the reflection layer 24 and circularly polarized counterclockwise. Then, the external light circularly polarized in the counterclockwise direction is converted into light in a second direction (shown by a vertical arrow in Fig. 4A) crossing the first direction via the phase delay layer 15 again. Thus, the external light in the second direction can not pass through the linearly polarized light pattern 12a of the pattern layer 12, so that the external light OL is prevented from being reflected by the reflective layer 24 and being emitted to the outside.

As described above, when the flat panel display 1 is in a turned-on state, the display light DL is emitted toward the display surface side by the optical film 10 and the reflective layer 24, and the external light OL is reflected toward the display surface side Not released.

On the other hand, as shown in Fig. 4B, when the flat panel display 1 is in the turned off state, the light emitting layer 23_off does not emit display light (DL in Fig. 4A).

Then, the external light OL is reflected by the transflective pattern (12b in Fig. 2) of the pattern layer 12. That is, when the flat panel display 1 is in the turned off state, part of the external light OL reflected by the pattern layer 12 is emitted toward the display surface side, thereby functioning as a mirror.

As described above, the flat panel display according to one embodiment of the present invention includes the optical film having the separate semi-permeable layer for transmitting the display light and reflecting the external light, and the adhesive layer for removing the adhesive therefrom, And the luminance can be prevented from being lowered by the semi-transparent layer.

Next, with reference to Figs. 5, 6 and 7, a method of manufacturing an optical film according to an embodiment of the present invention will be described.

FIG. 5 is a flowchart showing a method of manufacturing an optical film according to an embodiment of the present invention, and FIGS. 6 and 7 are process diagrams of FIG.

As shown in FIG. 5, a method of manufacturing an optical film according to an exemplary embodiment of the present invention includes a step (S11) of forming a base layer, a step (S12) of forming a pattern layer on at least one side of the base layer, (S13) forming a first and a second cover layer covering the pattern layer on both sides of the first and second cover layers, and forming a phase delay layer (S14) on one surface of the first and second cover layers.

6A, in the step S11 of providing the non-extension base layer 11 ', the non-extension base layer 11' is unwound from the film storage portion 31, and the swelled portion 32 to swell the unwounded non-drawn base layer 11 '. At this time, the swelled non-smoothing base layer 11 'expands the space between the polymer chains due to swelling, so that the light absorbing material is easily adsorbed. For reference, the unstretched base layer 11 'may be a PVA film.

As shown in Fig. 6 (b), the pattern layer 12 is formed on at least one surface of the swelled unoriented base layer 11 '. (S12)

That is, by using two or more material discharging portions 33a, 33b, and 33c that emit different materials, the light absorbing material is dyed on at least one surface of the swollen unstable base layer 11 ' do. Here, the light absorbing material is for forming a linearly polarized light pattern (12a in Fig. 2), and the metal dispersing material is for forming a transflective pattern (12b in Fig. 2). Thereby, the semi-transparent pattern 12b made of the metal dispersing material coated on at least one surface of the non-smoothing base layer 11 'is formed.

Any one of the material discharging portions 33a, 33b, and 33c may emit a boric acid solution for crosslinking the molecular structure of the unoriented base layer 11 'together with the light absorbing material.

In addition, in the step of forming the pattern layer 12, two or more material discharging portions 33a, 33b, and 33c are provided in the same chamber and are driven together to apply the light absorbing material, the boric acid solution, and the metal dispersing material simultaneously .

The metal dispersing material may be at least one selected from the group consisting of Ag, Au, Cu, Al, Pt, Ni, Pb, Co, Rh, An electrolyte including at least one of Ru, Sn, Ir, Pd, and Ti, or WGP (White Gold Plated metal).

In addition, at least one of the particle size and the coating ratio of the metal dispersing material can be adjusted so that the light transmittance of the optical film is 40 to 60%. In one example, the particle size of the metal dispersant may be between 5 and 150 nm.

Next, as shown in Fig. 6 (c), the unstretched base layer 11 'is stretched in one direction using the stretching portions 34a and 34b.

The base layer 11 is formed and the light absorbing material adsorbed on one surface of the base layer 11 is rearranged in a straight line shape in one direction, A linearly polarized light pattern 12a is formed.

At this time, the first and second cover layers 13 and 14 may be formed on both sides of the base layer 11 together. (S13)

Thereafter, as shown in Fig. 7, the phase delay layer 15 is formed on one surface of any one of the first and second cover layers 13, 14. (S14)

As described above, in the method of manufacturing an optical film according to one embodiment of the present invention, instead of attaching a separate transflective layer for semi-transmission of light to the polarizing layer, Thereby forming a semi-transparent pattern. Thus, the manufacturing time can be shortened, and the manufacturing process can be further facilitated.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of.

10: optical film 11: base layer
12: pattern layer 13, 14: first and second cover layers
15: phase delay layer
12a: linearly polarized light pattern 12b: semi-transparent pattern, metal fine particle
1: Flat panel display device 20: Flat panel display panel
21, 22: first and second substrates
23: luminescent layer 24: reflective layer

Claims (15)

An optical film that can be provided on a display surface of a flat panel display,
A base layer;
A pattern layer formed on at least one surface of the base layer;
First and second cover layers formed on both sides of the base layer to cover the pattern layer; And
And a phase delay layer formed on one surface of the first and second cover layers,
The pattern layer
A linearly polarized light pattern formed of a light absorbing material adsorbed on at least one surface of the base layer and stretched in one direction together with the base layer, the light absorbing material being rearranged to have a linear shape in one direction; And
And a semi-transmissive pattern formed of a metal dispersant applied on at least one side of the base layer. The method according to claim 1,
An optical film corresponding to at least one of the particle size and the coating rate of the metal dispersing material and having a light transmittance of 40 to 60%. 3. The method of claim 2,
Wherein the particle size of the metal dispersant is 5 to 150 nm. The method according to claim 1,
The metal dispersant may be at least one selected from the group consisting of Ag, Au, Cu, Al, Pt, Ni, Pb, Co, Rh, An optical film formed of an electrolyte containing at least one of ruthenium (Ru), tin (Sn), iridium (Ir), palladium (Pd), and titanium (Ti), or WGP (White Gold Plated metal). The method according to claim 1,
Wherein the light absorbing material is an iodine composite material. A method of manufacturing an optical film that can be provided on a display surface of a flat panel display,
Providing a base layer;
Forming a pattern layer on at least one side of the base layer;
Forming first and second cover layers on both sides of the base layer to cover the pattern layer; And
Forming a phase delay layer on one surface of the first and second cover layers,
The step of forming the pattern layer
Absorbing a light absorbing material on at least one side of the base layer;
Applying a metal dispersant on at least one side of the base layer so as to form a transflective pattern selectively transmitting light; And
And stretching the base layer in the one direction so that the light absorbing material adsorbed on at least one surface of the base layer is rearranged in a straight line shape in one direction to form a linearly polarized light pattern. The method according to claim 6,
In the step of applying the metal dispersant,
And adjusting at least one of a particle size and a coating ratio of the metal dispersing material so that a light transmittance of the optical film is 40 to 60%. 8. The method of claim 7,
In the step of applying the metal dispersant,
Wherein the particle size of the metal dispersant is 5 to 150 nm. The method according to claim 6,
Wherein the step of adsorbing the light absorbing material and the step of applying the metal dispersing material are carried out simultaneously in one chamber. delete The method according to claim 6,
In the step of applying the metal dispersant,
The metal dispersant may be at least one selected from the group consisting of Ag, Au, Cu, Al, Pt, Ni, Pb, Co, Rh, Wherein the film is formed of an electrolyte containing at least one of Ru, Sn, Ir, Pd and Ti, or WGP (White Gold Plated metal). In a flat panel display including a mirror function,
A flat panel display panel for emitting display light for displaying an image on a display surface; And
And an optical film formed on a display surface of the flat panel display panel to emit the display light to the outside and selectively reflect at least a part of external light,
The optical film
A base layer extending in one direction;
A pattern layer formed on at least one surface of the base layer;
First and second cover layers formed on both sides of the base layer to cover the pattern layer; And
And a phase delay layer formed on one surface of the first and second cover layers,
The pattern layer
A linearly polarized light pattern formed of a light absorbing material adsorbed on at least one surface of the base layer and stretched in the one direction together with the base layer and having a linear shape in one direction; And
And a semi-transparent pattern formed of a metal dispersing material coated on at least one side of the base layer. 13. The method of claim 12,
Wherein a light transmittance of the optical film corresponds to at least one of a particle size and an application ratio of the metal dispersant, and is 40 to 60%. 14. The method of claim 13,
Wherein the metal dispersing material has a particle size of 5 to 150 nm. 13. The method of claim 12,
The metal dispersant may be at least one selected from the group consisting of Ag, Au, Cu, Al, Pt, Ni, Pb, Co, Rh, An electrolyte comprising at least one of Ru, Sn, Ir, Pd and Ti, or WGP (White Gold Plated metal).

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